In electrical or electronic systems, various individual system modules, for instance various electronic/electric assemblies, various electronic/electric components, for instance various semiconductor components such as integrated circuits, etc., various subcomponents, provided in one and the same component or integrated circuit etc., communicate via a transfer medium such as a bus system.
A bus system may comprise one or more transfer lines. Bus systems can be used jointly by several, in particular by two or more than two devices of a respective system.
Many conventional bus systems comprise several partial systems, for example, a data bus, consisting of one or more data lines, and/or an address bus, consisting of one or more address lines, and/or a control bus, consisting of one or more control lines, etc.
In comparison to this, other bus systems are of a much simpler construction. For example, a so-called IBCB bus (IBCB=Inter Block Communication Bus) in general merely comprises two transmission lines to connect two respective devices.
Further examples for relatively simple bus systems are CAN busses (CAN=Controller Area Network), which generally only comprise two or three lines (e.g., CAN_HIGH, CAN_LOW, and—optionally—CAN_GND (ground)), LIN busses (LIN=Local Interconnect Network), which generally comprise only one single transmission line, etc.
In many conventional systems, for instance, in systems with an IBCB bus, various devices may be connected in a chain-like structure. For instance, a first component may be connected via two IBCB transmission lines to a second component, the second component may be connected via two IBCB transmission lines to a third component, the third component may be connected via two IBCB transmission lines to a fourth component, etc. Hence, e.g., a logical “1” (or correspondingly, a logical “0”) may first be transmitted from the first component to the second component in the above chain of components, then from the second component to the third component, then from the third component to the fourth component, etc.
In addition, a central microprocessor or microcontroller may be provided, which e.g., may be connected with the first (or last) component in the above chain of components, e.g., via SPI (SPI=Serial Peripheral Interface), or any other suitable connection.
The above system, i.e., the above devices connected via the above IBCB bus, and/or the above central microprocessor or microcontroller may, e.g., be used to control a battery, and/or the cells of a battery, for instance, the battery of a respective vehicle such as a car.
To avoid that the above devices themselves consume too much energy from the battery, especially during periods of time when they are not needed, they might be brought into a power saving mode/power down mode.
To bring the devices back from the power saving mode/power down mode to a normal operating mode (“wakeup”), the above devices may be provided with so-called wakeup receivers.
Wakeup receivers may, e.g., be adapted to detect by use of respective comparators detecting absolute signal levels on the IBCB bus that a specific dedicated wakeup signal sequence was sent, and may, in return, trigger that a respective device is brought back from the power saving mode/power down mode to a normal operating mode (“wakeup”).
However, the wakeup receivers themselves may consume a considerable amount of energy from the battery, even when the system is in the above power saving mode/power down mode.
For these or other reasons there is a need for an improved system, an improved wakeup receiver circuit, and an improved method to wakeup a device.